Getting something out of nothing: the search for Europa plume signatures in Galileo particle data

Hans Huybrighs
Max Planck Institute for Solar System Research

Abstract.
Recent Hubble Space Telescope observations hint at the existence of recurring water vapour plumes erupting from Europa’s surface. The significance of this phenomena is that by taking samples of these plumes from a flyby mission we could get access to Europa’s potentially habitable ocean, without even having to land.

Indisputable (in-situ) observations of these plumes have not been reported yet. However, it may be possible that the NASA Galileo mission encountered these plumes when it was active in the Jupiter system (1995 to 2003).

We present an overview of in-situ data obtained by the Galileo spacecraft during the Europa flybys. The data is compared in the context of the search for signs of active plumes. Focus is in particular on the data obtained with the plasma instruments PLS (low energy ions and electrons) and MAG (magnetic fields).